Slide-valve



(No Model.) 3 sheets-sheet 1. E. LESLIE.

SLIDE VALVE.

No. 425,681. Patented Apr. 15, 1890.

ATTORNEY (No Model.) 3Sheets-Sheet 3.

E; LESLIE. n SLIDE VALVE.

.No. 425.681. Pate n ted-Apr. 15, 1890.

ATTORNEY THE moms PETER! 00., moro-uwm, wlsmnaruu, n. c.

UNITED STATES PATENT OFFICE.

LESLIE BROTHERS MANUFACTURING COMPANY,

JERSEY.

OF PATERSON, NEYV SLI DE-YALVE.

, SPECIFICATION forming part of Letters Patent No. 425,681, dated April 15, 1890.

Application filed January E4,

To all whom it may concern:

Be it known that I, EDWARD LESLIE, of Orangeville, in the county of Dufferin, Province of Ontario, and Dominionfof Canada, have invented a new and Improved Slide- Valve, of which the following is a full, clear, and exact description.

The invention relates to slide-valves composed of an inner valve for controlling the exhaust and of an outer valve for controlling the inlet of the motive agent.

The object of the invention is to provide a new and improved slide-valve which is simple and durable in construction, very efiective and easyin operation, and permits of being run at a high rate of speed, preventing the unseating of the outer valve.

The invention consists of an outer valve provided with a loose top plate and an inner Valve having play or lost motion in the outer valve, and provided with top ridges, on which 3 is a transverse section of the same on the;

rests the said top plate. I

The invention also consists in certain parts and details and combinations of the same, as

will be fully described hereinafter, and then pointed out in the claims.

Reference is to be had to theaccompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a sectional side elevation of the improvement. as applied. Fig. 2 is a like view of the same ina different position. Fig.

line w a; of .Fig. 1. Fig.4 is an inverted plan view of the improvement. Fig. 5 is a plan view of the valve-seat, and Fig. 6 is a perspective view of the inner valve.

The valve-seat A is provided with the usual induction and edu-otion ports B and C and the exhaust-port D. On the valve-seat A is held to travel the sl1de-valve E, composed of an inner valve F and an outer valve G, which latter consists of an open rectangular frame,

on which fits a yoke H, to which is secured at one end the valve-stem I, connected with suitable mechanism for moving the valve E forward and backward over the ports on the valve-seat A. In the open top of the outer valve G fits a plate J, preferably provided in its ends and sides with spring packing-plates K, so as to form a steam-tight joint between a the outer valve G and the said plate J. The inner valve F is provided on its top with longitudinally-extending ridges F, on top of which rests said top plate J. The ridges F form spaces F on top of the inner valve F, so that the motive agent can pass from one end of the valve to the other. The inner valve F is of the same Width as the inside of the outer valve G,but the length of the inner valve is somewhat less, so as to form suffioient play or lost motion at either end, whereby the inner valve remains stationary during a certain time of the forward and backward stroke of the outer valve G, as hereinafter more fully described. The ends a and b of the outer valve G travel over the ports B and C, and in the sides 0 and d of the said valve, on the under side, are formed longitudinally-extending grooves e, registering at all times with openings D, leading into the exhaust port D. The grooves e extend nearly throughout the length of the sides 0 and d, so that the under side of the said outer valve is connected by the said grooves with the exhaust-port D, and consequently the suc tion in the latter removes the pressure from the under side of the outer valve, so that an unseating that is, a lifting of the valve against the pressure of the live steam in the steam-chest-is prevented. At the same time if any steam from the steam-chest works under the outer vahve G, it passes into the grooves o and to the exhaust-port D. This steam consequently does not exert an upward pressure against the valve G to unseat it.

\Vhen the valve E is in the position shown in Fig. 1, it is near the end of its right-hand stroke, and the motive agent passes from the steam-chest through the open port B into the left-hand end of the cylinder. The piston in the latter is then moved to the right in the direction of the arrow at, and when it is desired to out off the valve-stem I travels in the inverse direction of the arrow a, so that the end a of the outer valve G passes over the port B and cuts it off from connection with the steam-chest. During this motion of the outer valve G the inner valve F remains stathe outer valve G strikes theinnervvalve F is 1 free to slide upward on agent in the rightcan fully exhaust port 0, the valve F,

tionary, and the motive hand end of the piston through the entirely-open and into the exhaust-port D. When the end a of the outer valve G is cut off from the port B, then the other end bcomes in contact with moved with the outer valve in the inverse direction of the arrow at.

The ports 0 and D remain connected with.

each other until the piston has moved to the end of its stroke, takes place in the cylinder. The right-hand end of the valve F is then entirely across the port 0, so that the end I) of the outer valve G opens the port 0 to the steam-chest. Before this takes place the port B is connectedby the inner valve F with the exhaust-port D, so that when the piston commences its return-stroke the inner valve F fully connects the port B with the port D in the same manner as the ports 0 and D were formerly connected, as illustrated in Figs. 1 and 2. The motive'agent then enters through the port 0 into the righthand end of the cylinder and forces the piston to make its return-stroke.

When the outer valve G is to cut olf .with its end b over the port 0, then the valve-stem I moves in the direction of the arrow at, so as to move the outer valve G in the same direction, but the inner valve F remains stationary to fully exhaust the cylinder through the ports B and D. The valve F remains stationary until the end a strikes against the left-hand end of the inner valve, and then moves it to the position shown in Figs. 1 and 2.

It will be seen that when the valve E is in the position shown in Fig. 1 and the outer valve G travels in the inverse direction of the arrow a, as above described, then themotive agent, entering through the port B, can pass, when the said end is in about the middle of the port, into the interior of the outer valve G and through the spaces F to the right-handend of the inner valve F, so that a steamcushion is formed around the inner valve F, whereby the force with which the end I) of somewhat broken.

It is understood that the inner valve F remains stationary on account of the motive agent surrounding the inner valve, as before described. The outer valve G any extent without effecting the yoke II, carrying the valve-stem I, as the said yoke is the outer valve. The wear of the inner valve F chest. Consequently the plate J is resting very lightly on the ridges F of the inner valve, so

from the inner valve F. i I

so that a complete exhaust can wear to is taken up by the top plate J pressing on the ridges F by the f as to reduce the friction to a minimum, when the outer valve travels with the plate J and the inner valve remains stationary. At the same time the plate J prevents the motive agent from rushing into. the respective port 13 or 0 when the outer valve 1G moves Having thus described my inventiomwhat I claim as new, and desire to secure by Letters Patent, isa 1. A slide-valve comprising an outer valve actuated by the valve-gear and controlling the inlet-ports,

themotive agent and adapted to be operated by the said outer valve, suflioient play or lost motion being had between the twovalves, and a plate fitted into the openftop ofj the outer an inner valve contained within the outer valve for controlling the exhaust of away valve and resting on the top of the inner W valve,

2. A slide-valve comprisingan outer valve operated by the valve-stem, atop plate held loosely in the said outer valve, and an inner valve having lost motion or play within the outer valve, and provided with top ridges on which rests the said top plate, substantially as shown and described. 1 y

3. In a slide-valve,an outer valve actuated by the valve-gear, and provided in the under side of its sides with grooves registering at all times with the exhaust-port, substantially as shown anddescribed. I I i 4. In a slide-valve,the combination, with an outer valve controlling the inlet-ports, of a yoke fitted around the said outer valve and adapted to slide upward, a valve-stem held on the said yoke, an inner valve contained within the outer valve and operated by the same, play or lost motion being held between the two valves, and a plate fitted in the open end of the said outer valve and resting on the top of the inner valve, substantially as shown and described.

5. In a slide-valve, the combination, with an outer valve controlling the inlet-ports, of a yoke fitted around the said outer valve and adapted to slide upward, a valve-stem held on the said yoke, an inner valve contained within the outer valve and. operated bythe same, play or lost motion being had between the two, ridges formed on top of the saidinner valve, and a platefitted into the top of. the outer valve and resting on the said ridges, substantially as shown and described.

6. A slide-valve comprising an outer valve formed by an open frame, aninner valve c011- trolled by the said outer valve, and provided in its under sidewith an exhaust-cavity and on its top with ridges, and a plate fitted into the open top of the outer valve, substantially as shown and described. The motive agent surrounding the inner against the under side 7. A slide-valve comprisinganouter valve formed by an open frame having in the bottom of its sides grooves registering at all times with the exhaust-port, an inner valve controlled by the said outer valve, and provided in its under side with an exhaust-cavity and substantially as shownand described.

too

on its top with ridges, and a plate fitted into the open top of the outer valve, substantially as shown and described.

8. In a slide-valve, the combination, with an outer valve controllin g the inlet-ports and having part of its under surface exposed to the exhaust-port, so .as to be held on its seat by the pressure of the motive agent inside of the chest, of an inner valve controlling the exhaust and contained within the said outer valve, and having lost motion or play with the latter, the said inner valve being held on its-seat by the pressure of the motive agent within the chest, substantially as shown and described.

9. In a'slide-valve, the combination, with an outer valve controlling the inlet-ports and havmotive agent inside the chest, substantially as shown and described.

EDWARD LESLIE. WVitnesses:

THEO. G. HosTER, O. SEDGVVICK. 

